Task solved but failing assert (3rd example)

Hello, I have following code that works as "solution" of the task, but it's failing 3rd example assertion. I don't know why...

def checkio(data):
    if len(data) >= 10:
        has_digit, has_upper, has_lower = (False, False, False)

        for char in data:
            if char.isdigit():
                has_digit = True
            if char.isupper():
                has_upper = True
            if char.islower():
                has_lower = True
            if has_digit and has_upper and has_lower:
                return True
    else:
        return False


Traceback (most recent call last):
  File "D:\Barbara\home_house-password.py", line 22, in <module>
    assert checkio('asasasasasasasaas') == False, "3rd example"
AssertionError: 3rd example